Is there a word to describe a person who is both of the following?
a) insidious - in the traditional sense...that they have a tendency to use or harm people in such a way that the victim does not realize that harm has begun and may not realize that it's been done until much later.
b) cunning, but licit -- someone for whom the ends justify even the most devious of means but ONLY insofar as the means are aligned with the letter of the law or with otherwise-accepted social norms (irrespective of whether said means are in alignment with the spirit of the law or with the nature and severity of the ends). A sleazy personal injury lawyer, a patent troll, and a professional plaintiff would all be examples of this.
There's a Russian word for this: коварный. Was wondering if there's an English equivalent with matching nuance.
Please note: this is not a request for translation.